1. Technical Field
The present invention relates to a method, system, and product for monitoring of wearing surface layer thickness.
2. Related Art
Because tires are the only points of contact between a vehicle and the road, tires are one of the most crucial safety components in the vehicle, for all types of vehicles, such as cars, trucks, sport utility vehicles, off-road vehicles, airplanes, motorcycles, bicycles, mobile industrial and construction equipment, and the like. Tires are responsible for how the vehicle responds to the driving and steering. To optimize the effects of the tires on the road and therefore, to provide a safety behavior of the vehicle, the inflation pressure of the tires must be kept within the range given by the manufacturer. Tires that are driven under-inflated generate excessively high heat levels that can weaken the tire to the point of failure. At high speed, a rapidly deflating tire can cause loss of vehicle control. An over-inflated tire will result in harsh ride quality and will cause uneven tire wear. Furthermore, operating a vehicle with over- or under-inflated tires increases both fuel consumption and the exhaust emissions produced by the vehicle.
Tires are designed to grip the road, allowing the vehicle to start, stop and go around corners safely in any weather. Proper treads allow for normal handling of a vehicle and help prevent skidding and hydroplaning. The treads that accomplishes this wear out over time. As a consequence, the distance that is required to stop a vehicle increase with the wear of tires. A recent series of tests conducted for The British Rubber Manufacturers Association by MIRA has shown that the stopping distance significantly increases and cornering performance deteriorates when tire tread depth falls below 3 mm, even if the legal minimum tread depth is 1.6 mm (generally, the tire tread depth is comprised between 7 and 9 mm). So, it is extremely important to check the tire treads for signs of wear.
Generally, tires are manufactured with a “wear bar” that tells when the remaining tread depth is less than the minimum legally required e.g., 1.6 mm. When this wear bar can be seen, the tire must be replaced. Other known marking devices disappear when the wear of the treads becomes critical. However, a main drawback of these systems is that wear of tires must be done wheel after wheel, when the vehicle is stopped, according to a manual or visual analysis that is often painful due to the location of the wheels in the vehicle wings.
In other known methods, acoustic wear indicators emit a sound signal by coming into contact with the ground when the tires reach a wear threshold level. An automatic monitoring is done by using a detector consisting of a microphone placed beneath the vehicle and a processing unit switches on an indicator placed in the instrument panel. If such solution allows an automatic control of the tire wear, it closely depends upon the vehicle environment and driving conditions and therefore, it could be complex to implement.